Speed-reduction gearing



El. P. DU PNT 55m.. E59 QZQ,

SPEED REDUCTION GEARING Filed sept. 10. 1927 iatented dan. 15, i929.

etarra Ir Y maarre @EEB-REDUCTION GEAEING.

Application led. September 10, 1927. Serial No. 218,626.

lvfy invention relates to power transmission gearing and has for its purpose to reduce the speed between a driving shaft and a driven shaft. A more especial ob'ect is to 5 provide reduction gearing that wil operate quietly, avoid the necessity for bearings between the two shafts and provide a compact and simple unit of minimum length. An-

-other object of the invention is to so con-.

"i struct the gearing that it may be rendered operative as a speed reduction gearing or may be rendered4 inoperative when the driven shaft is ylocked to the driving shaft.

The invention is especially adaptedl to l5 automobile transmissions and its preferred `location is between the clutch-controlled driving shaft and the shaft that connects with the regular multiple-gear transmission, although it may be arranged to be applied 2e at any other point between the motor and rear axle. y

rlhe invention is an improvement on speed reduction gearing forming the subject-matter of an application filed by me June 24,

1227, Serial No. 201,051.

ln the drawings, which show a preferred embodiment of the invention and also' one preferred application thereof to an automobile transmission 1 is an elevational view showing the invention applied to an automobile transmission.

Fig. 2 is a longitudinal sectional view of reduction gearing embodying the invention.-

The driving shaft a. and the driven shaft are held in alignment by means of two aligning bearings carried by eccentrics z' and j fixed to, and projecting inward Afrom the ends of, a fixed housing h. Driving shaft a is slidable in the direction of its axis.

Shaft a carries a pinion c. Shaft 7J car ries aninternal gear g and teeth lc adapted is moved to the right, Fig. 2.

an intermediate rotary member spans the ends of shaft a and b. This member comprises an internal gear d, adapted to be engaged by pinion c when the latter is moved to the left, Fig. 2, and a pinion f,.which meshes with internal gear g 'on lshaft b. This rotary member, d, f, is mounted to turn on the eccentric bearingsvl and j.

Slidable shaft a is preferably formed as a sleeve splined on a shaft e. In Fig. 1 are 5' shown a clutch n for connecting the shaft of motor m to shaft e, and a housing o for a Ition, what l claim and 4desire toprotect by regular three-speed gear transmission (which may be connected to the rear axle p by the usual connections r).

B means of a grooved collar s fixed on sha t a and a hand lever t pivoted on housing It and engaging said collar, shaft a may be moved either to the left to bring pinion o into driving engagement with internal gear d, or to the right to bring pinion c into driv ing engagement with the teeth le on gear g.

When shaft a is moved to the left so as to engage pinion c with internal gear d, pinion c drives internal gear d and pinion f drives internal gear g, and shaft b is driven at a 70. reduced speed. That is, internal gear d, being of greater diameter than pinion q (carried by shaft a) will be driven at a lower speed than shaft an; and pinion f (turning with internal gear d), bein of smaller diameter than internal gear g carried by shaft b), will drive shaft b at a still lower speed. v

When shaft a is moved to the right so as to disengage pinion c from internal gear d and iixedly connect shafts a and b, the train of gearing d, f, g, becomes .inoperative to drive shaft b. Instead, internal gear g drives the rotary member f, al, at a higher speed, but the rotary member then acts as an idler. c

When my improved train'of gears is incorporated in an automobile drive, as shown in Fig. l, it will give, obviously besides the normal three speeds of the automobile,- threev additional speeds. I

internal gears run much more quietly than spur gears. Further, my arrangement of internal gears does not lengthen the lay-out as much as other arrangements of internal gears-that require bearing in between the driving and driven shafts. The unit is simple as well as compact. to be engaged by piston c when the latter The speed reduction gearing herein set forth has a slightly longer lay-out than the specific construction shown in my earlier ap plication, but it is of advantage thereover in that the housing is not rotatable. y

Having now fully described my inven- Lettersl Patent is:

1. Speed reduction gearing comprising a driving shaft and a driven shaft, ecoentrics in which said ,shafts are turnable, a pinion turning with one shaft, an internal gear turnable with the other shaft, an intermediate rotary member sleeved on said driving shaft and a driven shaft, eccentrics in which said shafts are turnable, a pinion turningwith one shaft, an internal gear turnable with the other shaft and provided with teeth adapted to be engaged by said pinion, an intermediate rotary member sleeved on said eccentrics and comprising a pinion in operative engagement with said internal gear and an internal gear adapted to be engaged by the first named pinion, and means to engage the first named pinion with the second named internal gear and disengage the first named pinion from said teeth, or, alternatively, lengage the first named pinion with said teeth and disengage the first named pinion from the second named internal gear.

3. Speed reduction gearing comprising a driving shaft and a driven shaft, one of said shafts being slidable in the direction of its axis, eccentrics in which said shafts are turnable, a pinion turning With the slidable shaft, an internal gear turnable with the other shaft and provided with teeth adapted to be engaged by said pinion, an intermediate rotary member sleeved on said eccentries and comprising a pinion in operative engagement with said internal gear and an internal gear adapted to be engaged by the first named pinion, and means to slide said slidable shaft in one direction to engage the first named pinion with the second named internal gear and disenga-ge the first named pinion from said teeth, and in the other di- A rection to reverse said connections.

4. Speed reduction gearing comprising a driving shaft and a driven shaft aligned therewith, fixed eccentrics in which the respectivevshafts turn, an intermediate rotary member sleeved on the eccentrics and spanning the two shafts, said member com` prising an internal gear and a pinion, a pin- 1 ion turning with one shaft, an iternal gear turning with the other shaft and in operative engagement with the -rst named pinion, a fixed housing carrying said eccentrics and enclosing the aligning ends of said shafts and the specified intermediate drivingmechanism, and means to engage the last named pinion with the first named internal gear so asto drive one shaft from the other through the medium of the intermediate driving connections specified, or, alternatively, to disconnect the last named 'pinion from the first vnamed internal 'gear and bring said shafts into direct driving engagement.

In testimony of whlch invention, I have hereunto set my hand, at Wilmington, Del.,

onthis 25th day of August, 1927.

ELEUTHERE PAUL DU PONT. 

